The present invention relates to the field of elevator control, and in particular to the communication of elevator reassignment information in a group elevator system.
Conventional group elevator systems include up and down buttons near the elevators for use by passengers when elevator service is desired. When one of these hall call buttons is pressed, an elevator that will most efficiently deliver the passengers in the desired direction is assigned. When the assigned elevator arrives at the floor on which the call occurred, a hall lantern above the assigned elevator illuminates to designate the elevator the passengers should enter. If the assigned elevator becomes unable to serve the passengers or is significantly delayed, the passengers must be assigned to a new elevator. This is accomplished by turning off the hall lantern above the originally assigned elevator, and illuminating the hall lantern above the newly assigned elevator when it arrives at the floor on which the call occurred. In addition, if a passenger is in an elevator when service of the elevator is terminated or when all floor requests have been fulfilled, the passenger may press a button on the car operating panel (COP) in the elevator to enter his or her floor request, or to exit the elevator and subsequently make a new hall call for a different elevator. While this is an effective system for reassigning passengers, these conventional systems suffer from the drawback of being unable to direct individual passengers requesting elevator service from the same floor in the same direction to different elevators.
Recently, elevator systems with destination entry have been introduced. In a destination entry system, passengers are required to register their destination floors before they are picked up. The group elevator system assigns each passenger to an elevator that most efficiently transports him or her to the desired destination floor. Passengers register their destination floors on destination entry devices, which are mounted near the elevators and can take the form of a numeric keypad or a touch screen display. The destination entry devices often include audio and visual capabilities, for example to verify a passenger's destination floor entry and to assist passengers with disabilities. However, because passengers enter their respective destination floors in short succession and are immediately assigned to different elevators, these systems do not include hall lanterns. Thus, passengers assigned to an elevator when its service is terminated must be alerted to the elevator assignment change. Also, in some destination entry systems, the COP in the elevator is either not accessible or non-functional. As a result, passengers in an elevator when service is terminated must be instructed as to how to get out of the elevator and to their desired destination.